As the demand for electricity grows, there is a need for power transmission conductors with increased current carrying capacity. The amount of power a transmission line can deliver is dependent on the current-carrying capacity (ampacity) of the line. However, a power transmission conductor's current carrying capacity is limited, in part, by its maximum safe operating temperature. Exceeding this temperature can result in damage to the conductor or to the transmission and distribution line accessories.
A conductor's temperature is determined by the cumulative effect of heating and cooling on the power line. The conductor is heated by Ohmic losses and solar heat and cooled by conduction, convection and radiation. The amount of heat generated due to Ohmic losses depends on the current (I) and the electrical resistance (R) of the conductor and is determined by the relationship that Ohmic losses=I2R. Electrical resistance (R) itself is further dependent on temperature with increasing temperatures increasing the resistance (R). As such, higher current and temperature leads to higher electrical resistance, which, in turn, leads to greater electrical losses in the conductor. Newly installed transmission lines can include heat emissive coatings. There is a need, however, for a system and a method to apply heat emissive coatings to existing power transmission conductors to increase their current carrying capacity. Such systems and methods can also be useful to apply other overhead conductor coatings.